This document describes the replication files associated with the paper:
Naoto Nonaka and Hirofumi Miwa. “Party Theory of Parliamentary Debate and the Endogenous Nature of Parliamentary Institutions: Theoretical Implications from Japan’s Diet.” Party Politics.

The following files are contained herein:
1_LDP_Study1.R (R code to replicate Study 1 using the data of the Liberal Democratic Party [LDP] members)
2_LDP_Study2.R (R code to replicate Study 2 using the data of the LDP members)
3_JSP_Study1.R (R code to replicate Study 1 using the data of the Japan Socialist Party [JSP] members)
4_DPJ_Study1.R (R code to replicate Study 1 using the data of the Democratic Party of Japan [DPJ] members)
5_DPJ_Study2.R (R code to replicate Study 2 using the data of the DPJ members)
6_ideal_point_estimation.R (R code to estimate the elite survey-based ideal points of Diet members)
7_ideal_point_validity_check.R (R code to check the validity of the elite survey-based ideal points)
Tobit_JAGS.R (JAGS code to estimate the parameters of the standard censored regression model)
random_effects_Tobit_JAGS.R (JAGS code to estimate the parameters of the censored regression model with random effects)
LDP_data_Study1.csv (LDP members’ data for Study 1)
LDP_data_Study2.csv (LDP members’ data for Study 2)
JSP_data_Study1.csv (JSP members’ data for Study 1)
DPJ_data_Study1.csv (DPJ members’ data for Study 1)
DPJ_data_Study2.csv (DPJ members’ data for Study 2)
UTAS_issue_items.csv (data to match variable names in the UTokyo-Asahi Elite Surveys to issues)
ideal_point_data.csv (data for the validity check of the elite survey-based ideal points [output of 6_ideal_point_estimation.R])
Miwa_2017_JJES.csv (Twitter-based ideal points from Miwa (2017))]
Nippon_Kaigi_data.csv (list of Diet members affiliated to the League of Diet Members for Nippon Kaigi)
name_correction_list.csv (list of Diet members’ name inconsistency to combine this study’s data with Catalinac’s (2018) data)
IRT_results.Rdata (posterior draws of the ordinal item response model [output of 6_ideal_point_estimation.R])
Seiron_data.csv (list of articles published in Seiron)
WiLL_data.csv (list of articles published in WiLL)
Voice_data.csv (list of articles published in Voice)

Each of the R codes works independently from other codes, but you need to get the following files and locate them in your working directory to run 6_ideal_point_estimation.R:
- UTokyo-Aasahi Elite Survey data for 2003, 2005, 2009, 2012, and 2014 general elections, which are available at the project’s website (http://www.masaki.j.u-tokyo.ac.jp/utas/utasindex_en.html)
You need the following files to run 7_ideal_point_validity_check.R:
- 2003_ideal_points.csv, 2005_ideal_points.csv, and 2009_ideal_points.csv, which are contained in Catalinac (2018)’s replication materials (https://doi.org/10.7910/DVN/PENDX4)

All R files are encoded in UTF-8. Some of them contain Japanese characters and will get garbled when opened with another encoding.

Please see Online Appendix A for information on packages and their versions used in our original analysis.

If you have any questions or concerns about the files, please contact Hirofumi Miwa.